Improvement in piano-fortes



(dlnitttl tant stent nettime,

WILLIAM BOURNE, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO HIMSELF A"ANDNATHANIEL CUMMINGS, OF SAME PLAGE.

Letters Potent No. 104,256, dated Jnnc 14, 1370.

IMPROVEMENT IN PIANO-FORTES.

The Schedule referred to in these Letters Patent and making peut of thesame MQW- 'I, WILLIAM Bomann, of Boston, in the county of Suffolk andState of Massachusetts, have invented certain new and usefulImprovements in Piano-Fortes, of which the following, taken inconnection with the accompanying drawing, is a specification.

Nutzt/rc and Objects of the Invention.

My invention relates to the damper by which thc vibration of the stringis checked when lthe linger is removed from' the key, and its object isto remedy many of the objections to the present over or upper damper,77so called, of the class in which long wooden levers or arms are arrangedabove the strings, to the lower edge of which are secured thedamper-pads o1' cushions, said levers, with the damper-pads, beinglifted by a small wire under their bac-k ends, the lower ends of whichrest upon the back ends of the keys.

In all over dampers77 ot' thisclass heretofore constructed, so far as myknowledge extends, the upper levers have been made long, extending backnearly to the tuning-pins, and their back ends rest upon felted buttonsupon the top of small wire rods, called damper-lifters, said wirespassing through holes in the iron fiame and the pin-block, and restingupon the back end of the key, but having no positive connectiontherewith.

The holes for the bearings of these wires have to be lined with cloth,and, as the pin-block is from two to three inches thick, of hard wood,it is quite a ditlicult and expensive job to bore the holes and linethem properly, and, when done, a very slight bend in thc lifter-wirewill cause it to stick and'bccome inoperative.

These lifter-wires not heilig connected to the kcy, but their lower endssimply resting upon the upper surface of the keys, or suspended abovethc keys with their lower ends raised a little above thc tops of thekeys, they are very liable to rebound when the key is struck, conveyingan unpleasant sensation to the operator, and it therefore becomesnecessary to load thc levers with lead to prevent the rebound, but thisdocs not entirely remedy the evil.

Another objection to this class of damper, as now constructed, is thatthe upper levers, extending back so near to the tuning-pins, interferevery much with the tuning of the piano, and, as the damper-pad issccured permanently' upon said levers, they cannot be removed withoutremoving the damper-pads, in which state the piano cannot be tunedproperly.

Another objection is that the damper-litters are very liable to bedisarranged and become inoperative, by being bent in drawing out andreplacing the action. Again, that portion of the key in the rear of thepivot has to be made so long that they are much more liable tor springand get out of place, and cause the liftcrs to interfere or becomeinoperative, and the extra weight of this long arm of the key makesthenction heavy to the touch, and necessitates loading the front end ofthe key with an ext-ra amount of lead to countcrbalance the same.

Another objection is that, owing to the damper-levers having no positiveconnection with the keys, they have to be so adjusted that their lowerends will not quite reach the upper surface of the keys, (to guardagainst or to reduce the liability of accident to them in drawing outand replacing` the act-loin) the result of which is that the keys haveto move a short distance before they come in contact with the lifters,and then the lifters move a short distance before the buttons on theirupper ends come in Contact lwith the upper levers, so that the keys haveto make three distinct movements or starts when struck by the operator.

Also, when using the loud pedal, the whole weight of the damper-leversis removed from the keys, thus making thc action much lighter, andconsequently, greatly impairing the power, quickness, and return of theaction.

Another kind of over damper, called the grand dampen7 is in use, inwhich the upper damper-levers are dispensed with, and the damper-padsare secured directly to the top ofthe damper-lifters, the lower ends ofwhich are so connected to the keys as to partake of the positivo motionof the keys, which is an improvement upon the damper first mentioned, inmany respects; but, owing to dispensing with the upper levers, thcdamper-pad is liable to vibrate with the string, and produces a sin gingsound which is very objectionable.

I have discovered by actual test that the application of a short upperdamper-lover to the grand-damper, the said levers rest-ing upon thedamper-pads, but not secured thereto, will remedy all of the objectionsmentioned as applicable to bot-h kinds of dampers described; and myinvention consists in the application to the grand damper i of a seriesof short wooden levers, secured by a hinge-joint to a light ii'ame andresting upon the damperpad, the damper-pad being secured directly to theupper end of the damper-lifter, as now used in thc grand damper.

` Description of thc Drawing.

Figure l is a plan of an instrument on a small scale, illustrating,r theapplication of my improvement.

Figure 2 is a section on line :t a: ou fig. 1.

The same letters refer to the same parts-in both of the figures.

Genera-l Description.

A is the case of theinstrumcnt;

B, the key; and

C, the key-rail.

D is the under damper-lever hinged to the block D', secured to the underdamper-trame a.

The key B has a groove or fork formed in its rear end, into which thetongue l), formed upon the forward end of the under damper-lever D,lits, as shown.

To the upper side of the under damper-levers D are hinged thedamper-buttons or blocks E, in the top.

ends ot' which are secured the damper-litters c c, which have bearingsin sockets formed in the thin plate F, placed in front of the pin-block,and near where Jthe hammer strikes the string.

vlo the upper ends of said damper-litters are secured Ithe damper-padsd, which rest upon the strings c.

G is the pin-block;

f, the tuning-pins;

g, the bridge; and

H, the sounding-board.

I is a light Wooden frame placed above the strings, to which aresecured, by screws, the flanges J, to which are hinged the upperdamper-levers L, so as to rest upon the damper-pads d.

7l is the stop-'rail to limit the upward movement of the upperdamper-levers L.

The operation of myimproved damper is as follows When the front end ofthe key is depressed by the touch of the operators finger, the front endof the under damper-lever is raised, and the damper-pad isV lifted fromthe string before the hammer strikes it,

and raises the upper damper-lever at the same time by its contacttherewith. When the key starts, the

under damper-levers, the damper-lifters, and the upper damper-levers allmove in unison therewith, the same weight being upon the keyallof thetime. \Vhen the finger is removed from the key its rear end fulls,carryingl with it the under damper-levers, the damperlifters, and thedamper-pads, the pads fallingupon the string's, and the upperdamper-lever, falling with the pad, serves to' keep the pad still afterit strikes the string, and eeotually prevents the singing sound which isso objectionable in the granddamper.

The upper damper-levers, and the frame to which they are secured, may bereadily removed without disturbing the damperepads, so that the pianomay be as readily and easily tuned as when the grand damper is used.

Claim.

Having thus described the construction and operation of my improvement,

What I cla-im as new, and desire to secure by Letters Patent of theUnited States, is-

The upper damper-levers L, constructed, arranged, and operating asherein set forth, in combination with the damper-pads d, secureddirectly tothe upper ends of the damper-litters c c, and operating by apositive connection with the key, substantially as described.

Executed at Boston this 27th day of April, 1870.

Witnesses:

N. C. LOMBARD, Gl.v E. WirrrNEY.

